The relative position and altitude of a person or object is important to monitor for many reasons. For example, in an artificial reality system, such as that disclosed in the above-identified copending patent application entitled "Method and Apparatus for Providing a Portable Visual Display," it is necessary to continually determine the direction a viewer is facing, the viewer's motion and the speed of the viewer's movements.
In the past, such measurements have been made using expensive, typically bulky, equipment.
In portable artificial reality systems, light weight and economy are mandatory since, in one embodiment, the viewer wears the directional sensor on a helmet, and in other embodiments carries the directional sensors in his/her hand.
Typically, such sensors are flux gate compasses, cameras, radio wave detectors and sensors, spring loaded acceleration devices, and other sophisticated devices, usually relying on magnetic flux detection or visual imaging. Also, usually such sensors require calibration each time a user begins a session using the device.
Thus, there is a need in the art for a positional sensor which is self contained, light weight and economical to manufacture.
There is a further need in the art for such a sensor which allows for positional determination and velocity calculations while still remaining portable and reliable.
There is still a further need in the art for such a sensor which requires no calibration upon initial use and which is without mechanical moving parts.